I WOULD LIKE TO KNOW,IF THERE IS A FREE TECHINCAL DATA IN SOMEWHERE ABOUT HOW TO CALCULATE THE DUCT DIAMETER OR CROSS SECTIONAL AREA WHILE CONSIDERING THE FLOW RATE AND THE PRESSURE. FOR INSTANCE, IN A VESSEL WE HAVE 2 ELECTRIC DRIVEN FANS WHICH SUPPLY 92,000 cbm/h AIR @ ATMOSPHERIC CONDITION...